


Shrimps are pretty rich

by Vandereer



Category: One Piece
Genre: Blow Jobs, M/M, Monsterfucking, Teratophilia, fishman au, i guess is what the official term is, really surprised monsterfucking isnt a tag wow okay, shrimpji, the world's riskiest blowjob
Language: English
Status: Completed
Published: 2019-10-24
Updated: 2019-10-24
Packaged: 2021-01-02 13:13:27
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,927
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21162209
Author URL: https://archiveofourown.org/users/Vandereer/pseuds/Vandereer
Summary: On his hunt across the Grand Line, Ace gets a little more than he was searching for when he finds a trapped fishman.Based on an au and art by watermelon-chan on tumblr!





	Shrimps are pretty rich

**Author's Note:**

> If you’ve seen Mel’s gorgeous art you probably know what this AU is about, if you don’t well. Shrimp fishman Sanji. Ace is gonna fuck that fish.  
There, now you’re all caught up. My song recommendation for this fic is Pools by Glass Animals just because.  
Enjoy!

Ace tiredly slaps at another enormous mosquito as it tries to land on his skin. That’s one thing that sucks about his choice to hardly ever wear a shirt, every bug in the swamp wants a taste.

He inhales and turns his body into a burst of bright flames and a cloud of burnt insects float down around him. At least his powers also prevent him from getting his feet wet as he turns the muddy swamp floor into dry path as he goes.

His search for Blackbeard had brought him to a few backwater locations before, but this place puts other backwater islands to shame. The thick ranks of trees with low-hanging clumps of feathery leaves force him to take out his knife to bushwhack a path through.

Then, he spots something that instantly lifts his spirits, a sign advertising the biggest shrimp boil ever seen before on the Grand Line. He licks his lips and crashes eagerly through the trees, into a clearing where he can smell frying sausage and some kind of broth.

A huge pot sits in the clearing, where a crowd of cooks are busy chopping onion, sausage and, disturbingly, some kind of toad into the bubbling broth.

Ace wanders up to the preparation table and asks one of the chefs, “Hey, where’s all the shrimp?”   
When he’d seen the words ‘shrimp boil’ he expected an enormous trough of the tiny creatures, all waiting to be poured into the pot in a steamy, delicious avalanche.

The man Ace assumes to be the head chef, with his tall hat made out of swamp twigs and what appear to be the skulls of some kind of rodent.

“You blind or somethin’?! Over there!”

Ace raises his eyebrows at the sight of an enormous creature sitting in a cage that’s hanging from a tree. It’s definitely not like any entrée he’s seen before. 

It’s underbelly is such a vivid shade of orange-red that it almost hurts to look at, and the hard shell a bright green with swirls of teal and yellow, like a hunk of malachite. Though his lower half definitely says ‘seafood’, his upper half looks more like a slender, nicely toned young man with a head of straight blonde hair and an elegantly curled pair of brows.

When the fishman rolls his eyes and sighs, Ace can see a flash of white razor-sharp teeth. The red antennae framing his face twitch up and down in annoyance as he flicks his bright-blue gaze over to Ace.

“Hey, you. Do you have any tobacco?”

“W-what?”

“To-bac-co, that stuff humans smoke, you know?” He waves an empty pipe balanced between his sharp claws. “If I’m going to be boiled alive in a couple of hours, I’d at least like one last puff.”

“They’re going to eat you? But... you’re sentient! I’m literally talking to you right now!”   
“You think these idiots care? I’ve been trying to tell ‘em that for hours...”

The fishman wrinkles his nose at the cooks,“And also trying to convince them to add garlic, plus some seasonings that aren’t just salt and pepper.”

Ace chuckles and climbs onto a crate next to the cage. “You’re a cook?”

“A cook, and an ingredient at the same time it seems. Whenever I meet humans, the reaction is either to run away, or to try and covered me in dessicated coconut and fry me.”

“Well, to be fair, you  _ do _ look pretty delicious!” Ace waggles his eyebrows and smirks.

The shrimp man seems taken aback at first, then lets out a high, clear laugh that turns into a pleased purring growl.

“You have good taste, little man!”

He leans his arms on the bars of the cage and the fishman gazes at him curiously, fanning his antennae open to reveal a pair of elegant fins. 

“So, you want me to help you get out of there, or what?” Ace says.

“Perhaps. I assume you want something in return?”

“Not really - oh but if you’re a cook, maybe you could whip somethin’ up for me. It’ll probably be better than whatever swamp-kelp soup they’re bout to put you in. I think I saw a rat fall into it just now.”

“Sounds good to me, I haven’t been able to stretch out in  _ hours.”  _

He uncurls one of his many bright-red feet and has to poke it through the bars of the cage to stretch it out fully.

“That’s uh… a lot of legs to get cramps in. I’m gonna go look for a key, but you gotta promise to not eat me when I let you out of there.”

The fishman leans his head on the heel of one hand and closes his eye. Possibly in a wink, it’s hard to tell with his hair flopped over his other eye, “Only if you promise the same!”

Ace hops down off the box, feeling so stunned his feet refuse to work for a few seconds. Flirting with a giant shrimp fishman possibly isn’t the weirdest thing he’s ever done, but it definitely lands in his top three somewhere. 

He heads back over to the cook’s table and picks the chef with the most vacant look on his face to ask; “Hey, do you know where the key to the shrimp cage is?”

“Huh?!”

“I need to uh, throw some marinade on him, before we cook him.”

“Marinade?”

“It’ll make him taste better.”

He points out the key, which Ace feels like an idiot for realising is just sitting unguarded at the end of the cook’s table anyway.

When he gets back to the cage, the fishman is rattling the bars of his cage angrily and yelling at a pair of chefs carrying some kind of slimy cucumber between them as they head towards the pot.

“No, no, NO! That will ruin my flavour! If you’re going to eat me, at least do it right!” he snarls at the chefs.

“Man that shrimp sure is a chatty one.” one of the cooks says as he dumps the slimy thing into the pot.

The fishman is still fuming when Ace hops back onto the crate and shoves the key into the lock. He stares in amazement as the fishman pulls himself out of the cage, his body is even longer than Ace thought at first and there’s a series of loud pops as he straightens up.

“Ugh,  _ finally _ .”

“You want to kick some ass before you go?” Ace says, cracking his knuckles.

“Leave it to me…” the fishman says, raising a foreleg menacingly as he stares down the head chef, “They need to pay, for their crimes against cooking.”

“HEY, HOW’D THE SHRIMP GET OUT?” the head chef bellows.

With a hiss, the fishman flicks his elegant body around like a whip and unleashes a series of kicks so powerful the head chef goes rocketing away. With a casual flip of his tail, the rest of the chefs go flying into the preparation table and knock the huge soup pot off balance.

To Ace’s surprise, the fishman catches it before it can fall over.

“I don’t waste food, even if it tastes terrible.”

Ace laughs as they run back towards the trees, starting to pant as he sprints to keep up with the fishman’s many legs.

“By the way, what’s your name?”

“Sanji.”

“Ace, nice to meet ya!”

* * *

Ace breathes a sigh of relief as they finally leave the clammy, bug-infested canopy of the swamp and a gust of fresh ocean air greets them. He starts wandering down the beach, towards the rocks where Striker is waiting, not in any particular hurry when he’s in such interesting company. He has to look up to meet the eyes of the fishman.

“You’re a hell of a fighter! How’d you get captured anyway?”

Sanji’s tail flicks in annoyance and he folds his arms over his chest, “It was… too embarrassing.”

“C’mon, I won’t make fun of ya. Promise.”

Ace nudges the hard carapace of the fishman with his elbow, then yelps at the pain doing so causes. 

“Well… I wanted to make a certain dish, but one of the ingredients doesn’t grow underwater. So I came here to look for it. I don’t think any of those hicks had seen a fishman before, let alone well… an aberration like me. They snuck up on me while I was walking through the market, and covered up my gills until I passed out. When I woke up I was in that cage.”

“I’m sorry that happened to you. That sounds… really unpleasant.”   
“Being suffocated rarely is.” Sanji says dryly, “They seemed to think I planned on dragging them back into the ocean with me, to add to my human larder.”

“You have a human larder?”

“Wouldn’t you like to know?”

Sanji leans down and his teeth flash as he nips the air inches from the tip of Ace’s hat, the loud snap of his jaws makes his ears ring a little. 

“Hey now, what did we say about not eatin’ each other?” Ace folds his arms and waves a finger in Sanji’s face. He purrs with laughter.

“I don’t recall promising anything.”

“You couldn’t eat me anyway, I’m a Logia fruit user.”

Ace turns his arm into a pillar of fire and Sanji’s eyes glitter with interest.

“Oh, but if you happened to fall into the ocean, I could still eat you, easily.”

Ace’s stomach growls, “Speaking of eating, weren’t you going to cook for me? I only came here because I was huntin’ for a shrimp boil.”

“I’ll give you something far better.”

Sanji walks over to the beach and dives elegantly into the water, there’s a pause and then a huge boom, like underwater cannonfire. An torrent of water rises into the air and all kinds of seafood start falling down from the sky.

Ace applauds him when his big head pokes back out of the surface of the water. Sanji grins as he starts collecting up the stunned fish.

“You better start a big fire, human.”

* * *

Ace burps and picks his teeth with a tuna bone as he sits against a rock, with a pleasantly distended stomach. Every time he thought he couldn’t possibly eat another bite of seafood, Sanji flipped another amazing cut of swordfish onto the fire, or shoved a juicy pile of oysters in front of him. Day turned to night around them by the time Ace finally decided he was full.

“You’re right, that was  _ way _ better than any shrimp boil I’ve been to. Best seafood I’ve ever had.” Ace says, patting his stomach and smiling.

Sanji purrs happily, and his pale blue cheeks turn a little pink.

“I’m glad you enjoyed it.”

Sanji picks up a scallop shell to see if there's any meat left inside, while his fanned tail sweeps aside the rest of the mess from their enormous seafood dinner. Piles of lobster shells, scallops and hundreds of tiny shrimp carapaces go clattering off the rocks and into the ocean.

“How did you do that anyway, those kicks and that huge cannonball thing?”   
“I’m a Mantis Shrimp fishman, I have the most powerful claws in the sea.” Sanji says, with a casual snap of his claws, a gunshot-like bang echoes across the beach and smacks Ace in the face with a blast of air so fierce it knocks his hat off.

“But of course, I prefer not to use my hands. They’re a chef’s most powerful tools.”

Ace stares at him, eyes bugged out in shock as he puts his hat back on. 

“Man, that’s amazing Sanji… You’re not like any other fishman I’ve seen before.”

“Flattery will only get you so far human.”

“No, I mean… you literally don’t look like any other fishman I’ve seen before.”   
“...Oh. That’s a pretty long story.”

Sanji turns aside, telling him he probably doesn’t feel like going into it. 

The fishman narrows his eye at Ace. “You’re something of an aberration yourself, human. Whenever I go on land they’re always afraid of me. ”   
“Well, you’re too interesting to be scary, and honestly I think you’re kinda pretty!”

“Pretty…?”

“Well yeah!”

The pink on Sanji’s cheeks deepens to a deep rose, and the blush creeps down over the swirls on his neck. To his never ending amusement, the fishman has to bury his face in his claws to hide it.

“What’s the matter, no-one ever told you that before?”

“...No.” Sanji says, muffled by his hands.

Ace chuckles and gets to his feet, he’s fascinated by Sanji’s muscular blue skin and the rippling abs underneath. 

Sanji quirks his eyebrows at him as he puts his palm out and strokes his cool skin. The muscles underneath flutter and Sanji lets out a pleased humming growl.

“And here I was thinking you were just joking earlier.” Sanji says.   
“Nope, you're hot!"

He leans down to rest his big head on his claws and looks at Ace with half-hooded eyes and a lazy smile. “You better be careful throwing compliments at me.” 

“Yeah, what you gonna do, huh?”

The fishman darts forward to kiss him. Ace chuckles as his lips wrap around more or less his entire lower face, but his lips are so soft and warm he can’t complain. Ace yelps a little as Sanji pushes him over backwards, only for him to land in the safety of his huge arms. Sanji lifts him up until he’s at eye level and his sharp teeth go nipping down his sides. He writhes at the ticklish feeling and groans as one of Sanji’s claws come up to swipe between his legs.

Sanji’s teeth tug at his pants and Ace eagerly wriggles out of them, feeling a thrill as cool night air brushes his erection. Sanji stares at his waist and runs his tongue over his lips.

“Mm, you’re pretty big… for a human anyway.”

“Oof, you ever gonna give me a compliment that isn’t backhanded in some way?”

“I haven’t decided yet.”

Ace swallows hard as Sanji bares his teeth, but the tongue that pokes out from between the sharp points looks sinfully soft and wet. He bites his lower lip hard as the tip strokes up his chest, leaving a wet trail up his stomach. As his lips press into Ace’s shoulder, his claw absently strokes over his nipple, the move causes him to shudder in pleasure, even if the tip lightly scores the skin over his collarbone.   
“Hah- oh  _ fuck…”  _ Ace pants as Sanji’s huge tongue swipes over his cock.

“You’re awfully brave… Or awfully stupid.” Sanji says with a wicked grin, “I could bite you in half you know.”

“Right now… I’m willin’ to take that risk.” his voice is shaky as Sanji poises his tongue at the base of his shaft and presses hard as he licks him again.

Despite the more than ominous warning, Sanji is careful with his teeth as he takes Ace into his mouth and sucks. He wants badly to grab a fistful of the fishman’s hair and fuck into his mouth, but there’s at least thirty-two extremely sharp reasons why he shouldn’t. It takes so much energy to hold himself back that his hips shudder and his cock bounces with a few sudden twitches.

Sanji seems to sense what he wants, his fins extend with a flutter and his eyes twinkle with amusement. He smirks and opens his mouth wider, stretching out his tongue to let Ace grind against it. He happily takes the offer, leaning his arms on Sanji’s forehead and thrusting into his willing mouth. The pleasure rushing through him as he comes in Sanji’s mouth makes him wonder if he would even care if he got bitten in half at this point.

He’s still shuddering and groaning as Sanji’s tongue swipes over his thighs to clean up the mess, his back arches as the skillful tongue slips between his legs and briefly brushes over his ass. He definitely wants to get more acquainted with  _ that  _ feeling later.

Sanji puts him back down against a rock and smirks as he swipes his mouth with a claw, before he curls himself up in a self-satisfied way.

“What… about you?” Ace pants.

“You probably wouldn’t know where to begin.”

“Try me.”    
Ace grins and shuffles closer, eager to find out just what Sanji has between his legs, but he stops him with a leg pressed against his shoulder.

“Maybe… some other time. I have to go.”

“Wait, go where?”   
“Dry land and I don’t mix, you just saw what can happen. I don’t feel… safe here.”

Sanji uncurls himself and walks towards the beach, getting ready to dive back into the water. Ace scrambles to his feet, hastily shoving his dick back into his pants with one hand while waving Sanji back with the other.

“Wait, wait! Will I see you again?”

The fishman looks surprised. “I suppose… If you insist, come to a restaurant called the Baratie. Maybe I’ll cook for you again.”

The fishman glances back one more time before he disappears back into the ocean, leaving nothing but a slight ripple and a splash of moonlit water.

Ace sits down on the sand, the entire lower half of his body still throbbing with the attention Sanji’s hot tongue brought with it, and aching for more.

He falls backwards onto the sand and stares up at the stars, making a mental note to look for the Baratie as soon as he can. 

_ That better not be the only time, please GOD don’t let it be the only time! _

**Author's Note:**

> *Ace, about to let himself get sucked off by a creature with many, many razor-sharp teeth*  
“chuckles, I’m in danger!”
> 
> Fun fact: i started writing this literally just to procrastinate. I had fun tho.  
All credit for this wonderful au goes to trickstermel and kite, I’m just the asshat writing porn about it.  
I have SO many filthy monsterfucker ideas so there might be more but, we’ll see. I need to stop procrastinating now cya.


End file.
